Parameter identification of circuit models for lead-acid batteries under non-zero initial conditions

This paper presents an algebraic method for parameter identification of Thevenin's equivalent circuit models for batteries under non-zero initial conditions. In traditional methods, it was assumed that all capacitor voltages have zero initial conditions at the beginning of each test. This would require a long rest time between two successive discharging or charging tests, leading to very long test time for a charging cycle. In this paper, we propose an algebraic method which can extract the circuit parameters together with initial conditions. This would theoretically reduce the rest time to 0 and substantially accelerate the testing cycles.